DESIGN, DEVELOPMENT, AND MODELING OF PERFUSABLE HYDROGELS TO REGULATE CELL FATE AND BEHAVIOR IN 3D CONSTRUCTS

Abstract

Despite numerous promising preclinical in vivo models and several decades of clinical trials, the overwhelming majority of human drug trials have failed to translate into effective treatments for many diseases and disorders. Due to these failures, researchers have learned that there is a significant need to develop better human cell-based model systems for drug screening and basic research. To achieve this, it is necessary to control the presentation of biochemical compounds within 3D cell-laden scaffolds. In this dissertation, a reliable and customizable pump-perfusion system is developed and, in conjunction with computational modeling, utilized to perfuse a 3D hydrogel scaffold via embedded channels in order to provide predictable spatial and temporal control over delivery of soluble factors to cells within the gel. This platform is then used to demonstrate spatial control over soluble morphogen gradients and induce a spectrum of differentiation in mesenchymal stem cells embedded in a 3D hydrogel scaffold. Additionally, highlighting the versatility of this culture platform, a perfusable artificial artery seeded with human ductus arteriosus smooth muscle cells is engineered. The cell architecture and ability of the construct to undergo vasoconstriction is characterized and compared to native vessels. Finally, a unique, moldable hydrogel biomaterial is synthesized (gelatin methacrylate conjugated with an N-cadherin peptide) and used to support the formation of a neural network that can serve as a platform for studying neurological diseases. Overall, this work provides new methods to enable more robust control of stem cell differentiation and more effective, long-term 3D cell culture platforms that will allow researchers to better screen therapeutics and gain new insights into disease state pathophysiology.